Big Walk Train Puzzle: How to Unlock and Start the Train

Quick answer: You cannot activate the train at the station. Complete the five Blue Tower reward puzzles, create the key at the summit, follow every Key Cutter arrow, and insert the finished key at the train control console.

Before you start

The railway is part of Blue Tower progression. Set up one player to track rewards, one to carry the key when it appears, and one to read the next Key Cutter arrow.

1. Collect five Blue Tower puzzle rewards

Head to Blue Tower in the eastern half of the map. Complete five different challenge puzzles around the tower and collect every red-and-gold reward. The summit does not create the key until all five slots can be filled.

Confirm each reward is collected before leaving a puzzle.
Keep the team together for multi-player challenges.
Use landmarks to avoid repeating a completed puzzle.

2. Create the Blue Tower key

Climb to the top of Blue Tower and place the five rewards into the empty slots or pedestals. Once every position is filled, an unshaped Blue Tower key appears in the centre. Pick it up before leaving the summit.

3. Shape the key at five Key Cutters

Return to ground level and use the blue Key Cutter machines near the tower. Start at the cutter near the base. Each machine cuts the key and displays an arrow showing the next cutter.

Insert the key into the first cutter.
Read the arrow before running ahead.
Find the next blue cutter and insert the key again.
Repeat until all five cutters have shaped the key.

If the final console does not work, check that the key passed through every cutter in the arrow sequence.

4. Insert the finished key and start the train

Carry the carved key to the control building or red-stair platform overlooking the tracks. Insert it into the console. The island-wide railway is restored and the red train begins circling the island clockwise.

Train riding tips

Use the engine horn to call separated teammates.
The speed lever starts at maximum and can stop the train for regrouping.
Check the mini-map and timetable at the station or rear carriage.
Sprinting and jumping onto the moving train may unlock the Big Ride achievement.

Train puzzle FAQ

Can I start the train directly at the station?

No. Complete the Blue Tower reward, key, and cutter steps first.

How many rewards do I need?

Five rewards from different challenge puzzles around Blue Tower.

Why will the console not accept my key?

Make sure it was created at the summit and passed through all five Key Cutters.